Set Appliance State:
Gas Off
| Isolate Mains Power to appliance as per TOPs P4 |
Access and move the X21 connector on the RHS of the PCB back
but do not remove it, so that the contacts on the PCB are visible
Disconnect the plug at the spark generator and make safe
but do not remove it, so that the contacts on the PCB are visible
Disconnect the plug at the spark generator and make safe
Gas On
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Measure the voltage between the brown wire at
connection X21 on the PCB to a suitable earth point.
Voltage should be approximately 155V DC.
Apply a CH demand.
As the boiler reaches the sparking stage of the ignition
sequence the voltage should increase to approximately
400V DC or greater for 5 seconds before returning to 155V.
connection X21 on the PCB to a suitable earth point.
Voltage should be approximately 155V DC.
Apply a CH demand.
As the boiler reaches the sparking stage of the ignition
sequence the voltage should increase to approximately
400V DC or greater for 5 seconds before returning to 155V.

Isolate as per TOPs P4
and refit as necessary